How to Use PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses)

by Posted on

PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) is an evidence-based reporting guideline designed to improve the transparency, completeness, and reliability of systematic reviews (SRs) and meta-analyses (MAs). Unlike AMSTAR-2 (quality assessment) or ROBIS (bias evaluation), PRISMA focuses on standardized reporting rather than methodological rigor.

PRISMA: Step-by-Step Guide

1. Understand the PRISMA Components

PRISMA consists of:

  • A 27-item checklist (key elements to report).
  • A flow diagram (visualizes study selection process).

2. When to Use PRISMA?

✔ When conducting a new SR/MA.
✔ When evaluating an existing SR for completeness.
✔ For peer review (journals often require PRISMA compliance).

PRISMA Checklist (Key Items)

Section 1: Title & Abstract

  • Title: Identify as a systematic review/meta-analysis.
  • Structured Abstract: Include objectives, data sources, methods, results, and conclusions.

Section 2: Introduction

  • Rationale: Why was the review conducted?
  • Objectives: Clearly state research question (PICO format preferred).

Section 3: Methods

  • Protocol Registration: Was the review preregistered (e.g., PROSPERO)?
  • Eligibility Criteria: Define PICO (Population, Intervention, Comparison, Outcome).
  • Information Sources: List databases (PubMed, Embase, etc.) + search dates.
  • Search Strategy: Provide full search syntax (e.g., MeSH terms, keywords).
  • Study Selection: Describe screening process (e.g., dual reviewers, software used).
  • Data Extraction: Methods for collecting data (e.g., piloted forms).
  • Risk of Bias (RoB): Tool used (e.g., Cochrane RoB 2.0, Newcastle-Ottawa).
  • Synthesis Methods: Meta-analysis approach (fixed/random effects), heterogeneity tests (I²).

Section 4: Results

  • Study Selection: PRISMA flow diagram (see below).
  • Study Characteristics: Table summarizing included studies.
  • Risk of Bias: Present RoB assessment (e.g., graph, table).
  • Synthesis Results: Forest plots, effect sizes, subgroup analyses.

Section 5: Discussion

  • Summary of Evidence: Key findings.
  • Limitations: Study biases, heterogeneity issues.
  • Conclusions: Implications for practice/research.

Section 6: Funding

  • Conflict of Interest: Declare any financial/non-financial COIs.

PRISMA Flow Diagram

A 4-stage flowchart showing:

  1. Records identified (database + other sources).
  2. Records after duplicates removed.
  3. Records screened (title/abstract).
  4. Full-text assessed for eligibility.
  5. Studies included in review.

Example:

Copy
Identification → Screening → Eligibility → Included  
   (n=5000) → (n=3000) → (n=100) → (n=50)

(The PRISMA Group provides a downloadable template.)

How to Apply PRISMA?

For Authors Conducting a Review

  1. Before starting:
    • Register protocol (PROSPERO).
    • Download the PRISMA checklist & flow diagram template.
  2. While writing:
    • Fill in each checklist item (e.g., “We searched PubMed, Embase…”).
    • Generate the flow diagram (use tools like Lucidchart, PRISMA2020).
  3. Before submission:
    • Cross-check manuscript against the checklist.

For Readers/Reviewers Evaluating a Review

✔ Check if the manuscript follows PRISMA guidelines.
✔ Look for missing items (e.g., no search strategy = red flag).

PRISMA 2020 Updates

The PRISMA-2020 version includes:

  • New items (e.g., equity considerations, reporting automation tools).
  • Revised flow diagram (now includes “database registers”).

PRISMA vs. AMSTAR-2 vs. ROBIS

Feature PRISMA AMSTAR-2 ROBIS
Purpose Reporting guideline Quality assessment Bias assessment
Use Case Writing SRs Appraising SRs Detecting bias in SRs
Output Checklist + flow diagram Confidence rating (High/Low) Risk of bias (Low/High)

Strengths of PRISMA

✔ Standardizes reporting (reduces “cherry-picking” of results).
✔ Improves reproducibility (detailed search methods required).
✔ Widely endorsed (required by top journals like BMJ, JAMA).

Limitations

✖ Does not assess quality (use AMSTAR-2/ROBIS for that).
✖ Time-consuming for authors (but improves rigor).

Conclusion

PRISMA ensures complete, transparent reporting of systematic reviews. Whether you’re conducting or evaluating an SR, following PRISMA guidelines enhances credibility.

Need a PRISMA checklist template or help filling it out? Let me know!

Published by oriaku